after defining new group, lost administration privileges and /etc/group has been changed

[NoOp]

On 03/02/2009 06:03 PM, Alan E. Davis wrote:
> Today I have been experimenting with permissions and groups between two
> systems to make it easier to share files on a USB drive between the two
> systems.
> 
> I defined a new group using the System -> Administration -> Users and Groups
> facility.  I noticed that, unlike my other system, no default group number
> was suggested.  So I defined the  new group with group id number 1111, which
> I reasons is high enough to not run afould of anything.
> 
> I logged out and back in.
> 
> When I click on System -> Administration -> Users and Groups, I am not
> longer allowed to access the tool.  The error message says I do nave
> permission to do so.  (I no longer remember the error message, because I
> have altered the permissions and groups resulting in a different message now
> being shown: "The configuration could not be loaded.  You are not allowed to
> access the system configuration."

Do you have a backup /etc/groups file? Check your /etc:

$ cd /etc
$ ls gr*

> 
> I had to add an admin group, but that didn't help, even adding my user name
> as a member.  I altered the sudoers file.

How did you alter it?

# /etc/sudoers
#
# This file MUST be edited with the 'visudo' command as root.

https://help.ubuntu.com/community/Sudoers

> 
> The groups in /etc/group do not have any other users assigned to any groups
> than those I assigned to the new group (1111) I made.  Admin is no longer a
> group!
> I have attached the new /etc/group file.
> 
> Thank you for any suggestions.  I would also appreciate your ideas of whom
> to ask, or which group.

Try the same method as with a lost password:
https://help.ubuntu.com/community/LostPassword
and then modify as root
https://help.ubuntu.com/8.04/serverguide/C/user-management.html